unit 6 - protein synthesis Flashcards
anticodon
3 bases on a tRNA that corresponds to a specific amino acid & complements the codons on mRNA
central dogma
genetic info flows in 1 direction: DNA - to RNA - protein
codon
3 base code in DNA/RNA that specifies a particular amino acid
deletion
type of mutation
- nucleotide is removed from the sequence (could form a frameshift)
exon
a segment of DNA or RNA molecule that codes for a protein
frameshift
mutation
- shift in the reading frame of codons on a mRNA molecule
- deletions & insertions can cause frameshifts
gene expression
appearance of a phenotype (physical feature) results from possession of a particular gene
insertion
insertion
mutation
- in which an extra nucleotide is added to the base sequence
- can cause frameshift
intron
a segment of DNA/RNA molecule that doesnt code for proteins
- interrupts sequence of genes
missense
a substitution mutation that results in coding for a different amino acid
mRNA
- messenger RNA
- carries genetic info from DNA in nucleus into ribosomes
mutation
permanent change in a cell’s DNA
nonsense
substitution mutation
- changes amino acid to “stop”
operator
negative/inhibitory regulatory site in genes that repressor proteins bind to inhibit synthesis of mRNA, and that protein
operon
a segment of DNA in which several genes with related functions are regulated by one promoter
repressor
substance that acts on an operon to inhibit mRNA synthesis
rRNA
ribosomal RNA
- molecule that forms part of the ribosome to help w translation
silent mutation
substitution mutation
- causes no change in amino acid and protein
transcription
the process by which mRNA is synthesized from a template DNA strand
translation
the process by which mRNA attaches to the ribosome & a protein is assembled with the help of tRNA
tRNA
type of RNA that transports amino acids to ribosome
